title: Expression profiles of carp IRF-3/-7 correlate with the up-regulation of RIG-I/MAVS/TRAF3/TBK1, four pivotal molecules in RIG-I signaling pathway.
abstract: The cytoplasmic helicase protein RIG-I (retinoic acid-inducible gene I) and downstream signaling molecules, MAVS (mitochondrial antiviral signaling protein), TRAF3 (TNF-receptor-associated factor 3) and TBK1 (TANK-binding kinase 1), have significant roles in the recognition of cytoplasmic 5'-triphosphate ssRNA and short dsRNA, and phosphorylation of IRF-3 (interferon regulatory factor 3) and IRF-7 which is responsible for the induction of type I interferons (IFN). In the present study, the full-length cDNAs of RIG-I, MAVS, TRAF3 and TBK1 were cloned and identified in common carp (Cyprinus carpio L.). The deduced protein of carp RIG-I is of 946 aa (amino acids), consisting of two CARDs (caspase-recruitment domain), a DEXDc (DExD/H box-containing domain), a HELICc (helicase superfamily c-terminal domain) and a RD (regulatory domain). Carp MAVS is of 585 aa, containing a CARD, a proline-rich region and a TM (transmembrane domain). Carp TRAF3 encodes a protein of 573 aa, including a RING (really interesting new gene), two TRAF-type zinc fingers, a coiled coil and a MATH-TRAF3 (meprin and TRAF homology) domain. Carp TBK1 is of 727 aa and contains a S_TKc domain (Serine/Threonine protein kinases, catalytic domain). Carp RIG-I, MAVS, TRAF3 and TBK1 mRNAs are ubiquitously expressed in all tissues examined. In response to SVCV infection, carp RIG-I and MAVS mRNAs were up-regulated at different levels in spleen, head kidney and intestine tissues at different time points. Similarly, both carp IRF-3 and IRF-7 mRNAs were significantly up-regulated in the detected tissues. Especially in intestine, the IRF-3 and IRF-7 mRNAs of carp increased and reached 25.3-fold (at 3 dpi) and 224.7-fold (at 5 dpi). Noteworthily, a significant growth of carp TRAF3 and TBK1 mRNA was also mainly found in intestine (7.0-fold and 11.3-fold at 5 dpi, respectively). These data implied that the expression profiles of IRF-3/-7 mRNAs in carp correlate with the up-regulation of RIG-I/MAVS/TRAF3/TBK, and carp RIG-I and MAVS may be involved in antiviral responses through the RIG-I viral recognition signaling pathway in a TRAF3/TBK1-dependent manner.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Feng
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.forename: Renqiu
authors.initials: R
authors.lastname: Kong
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
authors.forename: Yaping
authors.initials: Y
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Hu
authors.forename: Qionglin
authors.initials: Q
authors.lastname: Guo
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002347:Carps / Q000235:genetics / Q000276:immunology* / Q000821:virology; D003001:Cloning, Molecular; D053487:DEAD-box RNA Helicases / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D050838:Interferon Regulatory Factor-3 / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D050839:Interferon Regulatory Factor-7 / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D008969:Molecular Sequence Data; D010766:Phosphorylation; D010802:Phylogeny; D012313:RNA / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D016415:Sequence Alignment; D015854:Up-Regulation
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D050838:Interferon Regulatory Factor-3; D050839:Interferon Regulatory Factor-7; D012313:RNA; D053487:DEAD-box RNA Helicases